It's different. Most people on Twitter are there to promote their ideas and themselves, not get paid. So free syndication is fine for them. Most popular/quality YouTube content is there because the creator wants to get paid, not to spread their ideas.
… I mean, I think 99.99% of people are on twitter to have fun, not promote themselves. (Also some of the remainder are on twitter specifically to moan about bad customer service; it’s surprising how many accounts you we apparently used solely for this).
Similarly, most people on YouTube are not expecting to strike it big with videos of their cat, or their hobby project, or whatever.
Much of the content I watch on YouTube consists of obscure music videos where nobody is getting paid (or maybe they have a Patreon), but having someone else host your videos for free is still a pretty good deal.